The present invention relates to a coupling device featuring threaded members capable of rapid engagement and disengagement. Threaded coupling devices, such as nuts and bolts, have often proven ineffective in highly specialized applications, including by way of example, where speed is required, or where extended rotating movement is undesirable.
The coupling device of U.S. Pat. No. 5,378,100, issued Jan. 3, 1995, includes a first member provided with external threads and a second member having an opening therein into which the first member is inserted. The second member is provided with pluralities of movably mounted, internally threaded elements for receiving the external threads of the first member. The first member is inserted within the second member by rectilinear sliding movement, after which the first member is rotated into tight engagement with the second member. Release of the first member is accomplished simply by rotating same slightly in the opposite direction, after which simple manual manipulation of the second member withdraws the threaded elements from engagement permitting the first member to be slidably removed along an axial direction from the second member.
The prior coupling device which is the subject of U.S. Pat. No. 5,378,100 is illustrated in FIG. 1. This coupling device includes a first member 10 provided with threads 16 and a second member 12 having a threaded opening therein in which the first member 10 is inserted in locking relationship. The first member 10 is a bolt provided with a head 14 and helical threads 16 on the shaft thereof.
The second member 12 includes a sleeve 18 into which is slidably mounted a cylinder 20. The cylinder 20 is provided with a series of slots 22 through which corresponding keys 24 pass. The keys 24 are attached to the sleeve 18 with fasteners 26.
The cylinder 20 is provided with a frustoconical surface 19 which is a surface of revolution extending at an acute angle to the longitudinal axis of the sleeve 18 and cylinder 20 along which the first member 10 moves. A second frustoconical surface 21 is provided within the cylinder 20 extending at an acute angle to the longitudinal axis of the sleeve 18 and the cylinder 20.
A plurality of movably mounted externally threaded elements 28 are positioned within the lower cavity of the cylinder 20. The movably mounted threaded elements 28 are held in place and urged downwardly within the cavity 30 by the washer 32. The movably mounted threaded elements 28 are provided with internal threads 29 coaxial with the cylinder 20.
The second member 12 is provided with a cap 34 which is mounted for movement relative to the sleeve 18. The cap 34 includes a shoulder 36 provided with threads 38 which engage the threads 39 of the cylinder 20 permitting the cap 34 to be screwed in place within the cylinder 20. A hole 35 is provided in the shoulder 36 for receiving a locking pin 37 which passes through the hole 21 in the cylinder 20. In this manner, proper alignment of the cap 34 and the cylinder 20 with the slots 22 and key elements 24, sleeve 18 and the threaded elements 28 is ensured. A coil spring 40 is positioned within the gap 42 between the outer wall of the cap 34 and the inner wall of the sleeve 18. The spring 40 normally urges the cap 34 and the sleeve 18 in opposite directions.
A second coil spring 44 is positioned within the cavity 46 between the shoulder 48 of the cap 34 and the lip 50 of the washer 32. The second coil spring 44 normally urges the washer 32 downwardly such that the lip 50 engages the upper edges 54 of the movably mounted threaded elements 28.
Each of the threaded elements 28 includes at the top on the inner surface thereof a frustoconical surface 52 terminating at the upper portion in the edge 54 against which the bottom of the lip 50 of the washer 32 abuts. Each of the elements 28 is also provided with a frustoconical surface 55 extending at an acute angle to the axis of the sleeve 18, thus permitting easy sliding movement between the frustoconical surfaces 21 and 55.
Each of the movably mounted internally threaded elements 28 is provided near the bottom with a frustoconical surface 56 which abuts at an acute angle to the axis of the cylinder 20. The frustoconical surfaces 56 of the movably mounted threaded elements 28 are thereby adapted to axially abut and slide on the frustoconical surface 19 of the cylinder 20. Moreover, the frustoconical surface 56 of each of the elements 28 abuts the sloping surface 58 of each of the keys 24.
Each of the keys 24 protrudes through a slot 22 formed in the cylinder 20 and engages the sloping surface 56 of the movably mounted threaded element 28. Each of the threaded elements 28 is provided with a notch 57 defining the downwardly sloping contact surface area 56 which is complementary in configuration with respect to the downwardly sloping contact surface 58 of the key 24. Thus, as the cap 34 is manually moved closer to the sleeve 18, the keys 24 are moved upwardly causing the threaded elements 28 to move outwardly disengaging the threads 29 from the threads 16 of the first member 10.
From the foregoing it will be apparent that when the bolt 10 is moved inwardly along a rectilinear axis, i.e., without rotation, the threads 16 of the first member 10 engage the threads 29 of each of the threaded elements 28, moving same outwardly. After the first member or bolt 10 is pushed all the way into the second member 12, or as close thereto as may be desired or practical, the head 14 is manually rotated until the inside surface 61 of the head 14 abuts the lower surface of the sleeve 18, thus locking the first member 10 within the second member 12. Unlocking is accomplished as the top 34 and the shoulder 35 of the sleeve 18 are moved in close proximity to one another against the force of the first coil spring 40 promoting upward movement of the keys 24 while the sliding movement of the sliding surfaces 58 of the keys 24 and the supporting surfaces 56 of the threaded elements 28 move the threaded elements 28 outwardly away from each other in a radial direction thus releasing the engagement between the threads 16 of the first member and the threads 29 of the threaded elements 28, thus permitting the first member to be removed by rectilinear, sliding movement.
Rapid engagement and disengagement along a rectilinear axis is accomplished with the coupling members of the present invention, wherein there are featured pin assemblies movably fitted within adjacent V-shaped segments of the movably mounted external threaded elements, such that as the coupling members are moved relative to each other the pin assemblies force the threaded elements apart. In addition, ball assemblies are employed enhancing the locking action of the component parts while ensuring proper alignment thereof.